Hello Arthur,
Yes, it can be rather consuming (ok, not too much, but probably several days): I need to have all dialogs handling ofr this, need to add support for diferent themes, need to think about black on black and red on red, need to take into account that next thing people would say: whay it is not persistent between sessions etc.
From one side. From another side, using of the colors already blocked in my plans by another idea, which I think more useful. I woudl like to implement some how Color Visual theme for languages. So you would be able to assign color to language, and it would be used everywhere in interface. In menues, dialogs, tabs etc...
Maybe after implmenting of this idea, I can think about some color marking for files.
Thanks for suggestion.
Best regards,
Alex.